diff --git a/externs/closure-compiler.js b/externs/closure-compiler.js
index 21a3e954fd..b9c546b0ae 100644
--- a/externs/closure-compiler.js
+++ b/externs/closure-compiler.js
@@ -30,15 +30,3 @@ Touch.prototype.webkitRadiusX;
 
 /** @type {number} */
 Touch.prototype.webkitRadiusY;
-
-
-
-/**
- * @type {boolean}
- */
-WebGLContextAttributes.prototype.preferLowPowerToHighPerformance;
-
-/**
- * @type {boolean}
- */
-WebGLContextAttributes.prototype.failIfMajorPerformanceCaveat;